Experimental Studies of Nuclear Physics Input for \(\gamma \)-Process Nucleosynthesis

The predictions of reaction rates for the γ process in the scope of the Hauser-Feshbach statistical model crucially depend on nuclear physics input-parameters as optical-model potentials (OMP) or γ-ray strength functions.Precise cross-section measurements at astrophysically relevant energies help to constrain adopted models and, therefore, to reduce the uncertainties in the theoretically predicted reaction rates.During the last years, several cross-sections of charged-particle induced reactions on heavy nuclei have been measured at the University of Cologne.Either by means of the in-beam method at the HORUS γ-ray spectrometer or the activation technique using the Cologne Clover Counting Setup, total and partial cross-sections could be used to further constrain different models for nuclear physics input-parameters.It could be shown that modifications on the α-OMP in the case of the 112 Sn(α,γ) reaction also improve the description of the recently measured cross sections of the 108 Cd(α,γ) and 108 Cd(α,n) reaction and other reactions as well.Partial cross-sections of the 92 Mo(p, γ) reaction were used to improve the γ-strength function model in 93 Tc in the same way as it was done for the 89 Y(p,γ) reaction.